Looking for a basic router to set up VPN L2TP to connect back to a Unifi system

I have a unifi system and I want to set up a VPN on a 2nd router (off site) and send the traffic from various IoT devices back to the main site.

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I'd prefer do this with a Unifi Device, but I can't figure out how to set up a VLAN that would send all traffic back to the other site over VPN.

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I assume Mikrotik has a lower priced unit that could do this but I'm not sure what would be best.

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Thanks,

Bil